This invention relates to methods of fabricating filament-reinforced hollow bodies.
Hollow bodies can be fabricated by winding a suitable filament, e.g. glass or carbon-fibre, on to a mandrel having an appropriately shaped outer surface, the winding being impregnated with a suitable resin, e.g. an epoxy resin. The impregnation can be effected during winding, by using filament wetted by the resin or pre-impregnated filament ("pre-preg"), or subsequent to winding with dry non-impregnated filament. For some purposes a light-weight thin-walled body of large cross-section may be required, and the problem arises of obtaining such a body of adequate strength.
One method of strengthening such a structure is to provide it with one or more circumferential ribs or flanges located internally between the ends. Such ribs or flanges might be produced separately and stuck to the inner surface of a smooth body formed as above. However, the present invention provides a superior method by which the flanges are formed integrally with the body.